Automatically releasable couplings



Jan. 5, 1960 y L. SCHART 2,9

AUTOMATICALLY RELEASABLE COUPLINGS Original Filed Aug. 20. 1957 FIG. 2

INVENTOR Ludwig Scharr United States Patent Divided and this applicationJuly 28, 1958, Serial No.-

3 Claims. (Cl. 294-83) This invention relates to improvements inautomatically releasable couplings to separate an airbo'rne load from aparachute canopy. The load may consist of any type of cargo, or aircraftwherein the canopy is used to brake the speed of the aircraft; therelease operation of the coupling taking place when the landing speed ofthe aircraft has decelerated to a predetermined degree, or when thecargo makes contact with the ground.

The invention of this application is a division out of US. applicationSerial No. 679,232 filed August 20, 1957.

Automatically releasable parachute canopy couplings for use inconnection with droppingof cargo, and braking the landing speed ofaircraft are well known, including lo'ad connectable frames or parts andcanopy connectable parts and detent means to hold such parts together,including springs and other associated features.

In some couplings springs are used, the strength of which is calculatedby the force of the load pull. Mechanisms for unsafetying coupling partsare a feature of known couplings, but generally in such types ofcouplings strength of the spring must at least equal or be greater thanthe weight of the load shock only when the canopy has been inflated andstabilized so as to prevent premature release of the parts of thecoupling, such as during the deployment of the canopy after initialdischarge of the load. Where the load or pull, such as in dropping ofheavy cargo and fast landing speeds of the aircraft, is considerable, itis virtually impossible to furnish springs strong enough to preventpremature release of the coupling parts. It is therefore a purpose ofthe present invention to provide a coupling for cargo dropping canopiesand aircraft braking canopies which fulfills the requirements for a highload pull upon safetying the same and yet permit cheap and weight savingconstruction. To that end, the invention includes blocking elementsunder which predetermined load pull will unsafet-y the coupling onlyafter a proper degree of inflation of the canopy.

A further object of this invention is the provision of an automaticallyreleasable parachute canopy coupling for use in connection with thedropping of cargo loads and the braking of airplanes which includesrelatively connectable and releasable canopy attached and load attachedparts having associated therewith a blocking means which will place saidparts in condition for relative release, and which blocking means isoperated to enable such relative release of said parts only when theblocking means is subjected to a sufiicient shock force by a properlyairborne or inflated canopy to which the coupling is attached.

Other objects and advantages of this invention will be apparent duringthe course of the following detailed description.

In the accompanying drawings, forming a part of this specification andwherein similar reference characters designate corresponding partsthroughout the several views:

Figure 1 shows a vertical cross sectional view of a Patented Jan. 5-,1960 ice I coupling parts of the coupling still in connected relation-Figure 3 is a vertical cross sectional view of the parts of the form ofcoupling shown. in Figures 1 and 2, showing the canopy connecting partin readiness to detach itself from the load connecting part of thecoupling, due to load decrease, such as occurs when ground contact ismade by the cargo or incidental to slowing up of landing speed of anaircraft.

Figure 4 is a transverse cross sectional view taken substantially on theline 44 of Figure 1.

In the drawing, wherein fo'r the purpose of illustration is shown oneform of the invention, the letter A may generally designate the same asshown in Figures 1 to 4 of the drawings.

Referring to the form of invention A shown in Figures 1 to 4, inclusive,the load connecting parts are safetyed by means of a corrugated tube of.the Sylpho'n-bellows type, and the releasable detent means consists ofa segmentally divided ring, the parts of which are separable. Tothatend, I have provided a supporting frame which is in the shape of acylindrical shaped casing structure 50 having load connectable shaft orbolt 56 is releasably connected diametrically through the lower part ofthe frame 50 andthe insert 54, as shown in Figure 1, in 'order toreceive a.

cable connection 57 for a load.

Within the chamber 57 of the casing 50 is a sleeve or cylindrical member58 adapted to receive a compression spring 59 therein. The cylinder 58at its lower end is provided with a downwardly divergently flaringtapered seat 60 adapted to receive the segments 61 of the detent ring 61thereagainst. A corrugated collapsible tube 62 of the Sylphon-bellowstype rests at one end against the under side of the wall 51 and at itslower end upon the top wall of the cylinder 58. If desired, the end oftube 62 may be permanently connected to the cylinder. Normal expandedposition of the tube 62 is shown in Figure 1. In this position it holdsthe cylinder 58 in the position shown in Figure 1 so that the segmentsof the ring 61 are not collapsed under the force of spring 59. Thecanopy connectable bolt or member 53 is provided with a shroud lineconnecting head 62 which may be detachably screw threaded at 63 to theupper end of the bolt 53. The bolt 53 has a reduced intermediate shankportion 64. Its lower end is provided with an enlarged head 65 having aneck in the shape of an upwardly co'nvergently flaring ring seat 66.

The segmental blocks or members 61 of ring 61 are grouped around thebolt neck 66 when the parts are in load supporting position, and thehead 65 seats upon the wall 55.

In launching position, and on safety, the canopy bolt is positioned assho'wn in Figure 1. The corrugated tube 62 is deformable to the positionshown in Figure 2 when the load is airborne; the cylinder 58 slidingupwardly so its lower end is spaced from the wall 55 as shown in Figure2. When the proper load reduction occurs, as when the cargo hits theground, the spring 59 will force the segments 61 downwardly 01f of head65, permitting the bolt 53 to be released from its connection with thecasing or frame structure 50 (see Figure 3).

In assembling the load connection pin 56 is removed, as is also the cap54. The cylinder 58, together with the Sylphon-bellows are firstinserted in the relation shown into the chamber 57 and the spring 59 isalso inserted into the cylinder 58. The bolt 53, without its ring piece62, is then pushed in from below with the collar pieces 61 assembledupon its head 65 held assembled as by a split ring or rubber band orsome like expedient. Inasmuch as the segmental pieces 61 then restagainst seat 60, the bolt 53 may then receive its ring piece 62, whichis screwed into position for compressing spring 59. The cap 54 is theninserted and the cross bolt 56 then assembled.

Various changes may be made to the form of invention herein shown anddescribed without departing from the spirit of the invention or scope ofthe claims.

I claim:

1. In an automatically releasable parachute canopy coupling forsupporting cargo and other loads, the combination of a casing havingmeans at the bottom of the casing for attaching a load thereto, anelongated rigid bolt like member slidably disposed for movement withinthe casing, said member having a canopy connectable end extending fromthe casing, means to limit downward movement of the member with respectto the casing, said bolt like member having an upwardly facing shoulderdisposed within the casing, a segmentally divided split detent ringassembly engaging said shoulder and surrounding the lower part of thebolt like member adjacent said sho'ulder, a cylinder slidably mountedwithin the casing and having a lower end resting in releasableengagement against the segments of the divided ring and holding saidring in engagement with said shoulder, collapsible means in the casingengaging the cylinder and normally holding the cylinder downwardly inmember retaining engagement with the segments of said divided ring, andspring means under compression in the cylinder normally Zengaging saidsegments of the divided ring and biased to force them o'fi of saidshoulder after the cylinder :is

4 moved upwardly in the casing as a result of the load becoming airborneand when the load supported by the bolt like member has landed to enablesaid spring means to exert its ring segment releasing force.

2. In an automatically releasable parachute canopy coupling forsupporting cargo and other lo'ads, the combination of an elongatedtubular casing having a chamber therein, means at the bottom of thecasing for supporting a load, the casing having a top wall provided withan opening therein, an elongated canopy co'nnectable member movablyextending through said opening and having an outer end portion forattachment to a canopy and having a lower end portion within the casingchamber provided with an upwardly facing downwardly divergent taperedshoulder, means on thecasing to limit down- Ward movement of the memberwith respect to the casing, a segmentally divided ring releasably seatedupon said shoulder, a sleeve shaped member slidably disposed within saidchamber having a lower end engaging the segments of said ring shaped tohold them assembled upon said shoulder, yieldably collapsible andextensible means between the top wall of said casing and the top of saidsleeve normally holding the sleeve downwardly so that the sleeve willhold the segments of said ring against said shoulder, and compressedspring means within said sleeve engaging the tops of the segments ofsaid ring and biased to force said segments downwardly off of saidshoulder, after the sleeve is moved upwardly in the tube as a resultof'the load becoming airborne and when a load supported by said couplinghas landed to enable said spring-to exert its ring releasing force.

3. A coupling as defined in claim 2 in which the extensible meansbetween the top wall of the tube and the sleeve comprises a normallyexpanded Sylphon-bellows.

No references cited.

